Manufacture of staple fiber yarns from continuous filaments



Ap 13, 1937; 7 W. TAYLOR T AL 2,077,078

MANUFACTURE OF STAPLE FIBER YARNS FROM CONTINUOUS FILAMENTS Filed May 18, 1934 2 Sheets-Sheet 1 April 13, 1937. w. 1. TAYLOR Er AL 2,077,078

MANUFACTURE OF STAPLE FIBER YARNS FROM CONTINUOUS FILAMENTS Filed May 18, 1934 Q2 Sheets-Sheet 2 51 lam-N Ms 7 14 ATTORNEYS Patented Apr. 13, 1937 UNITED STATES PATENT OFFICE? MANUFACTURE OF STAPLE FIBER YARNS FROM CONTINUOUS FILAMENTS' Application May 18,1934, Serial No. 120,204 In Great Britain May 22, 193:

11 Claims.

This invention relates to the manufacture of "spun orstaple fiber yarn from continuous filaments, i. e., filaments of considerable length as r compared with the length of fiber required in J the yarn to be produced or as compared with the short, naturally-occurring fibers such as, for example, cotton or wool, the object of the invention being to produce such yarn in which the physical characteristics of the original filaments are to 10 a large extent retained, as well as to effect the production in a simple, expeditious, and cheap are readily cut with-only a light pressure exerted.

25 on them at the cutting surface. There is, therefore, only a light gripping action on the bundle, with the result that the filaments in the bundle are subjected to relatively low tension.

It will, therefore, be seen that the method of 30 the present invention is not one relying on the drafting of naturally-occurring fibers or fibers already formed by a cutting or like operation, nor yet on the other hand on the subjecting of continuous filaments to a tearing operation for the purpose of extending them to breaking point.

After cutting of a particular filament, a length of that filament passes the cutting surface uncut while cutting of other filaments is taking place, cutting thus being transferred from filament to 40 filament in the bundle until the particular filament is again out, and so on. The points of cutting being distributed among the filaments, the out filaments are transformed into fibers of an average length depending upon the frequency with which the filaments are cut. Such frequency, and consequently the average length of fiber, can be controlled by adjustment of various factors, e. g. by having a predetermined amount of twist in the bundle, as will appear later.

' 50 Movement of the surface in the same direction conversion of filaments in the material into fibers. Conveniently, the pressing of the filaments into contact with the surface having the cutting action is effected by means of a roller or the like also moving in the direction of motion of the filaments 5 so as to facilitate continued forward feed of the filaments. j

A rotatable roller forms a simple form of cutting surface, and for simplicity the member bearing the cutting surface will hereafter be generally referred to as a roller, it being understood, however, that the invention is not limited to the use of a roller. Likewise, the pressing member will be referred to as a pressing roller".

The pressing roller may move at the same speed as the cutting roller or at a different speed therefrom. For example, both rollers may, be positively driven at any desired speed providing, in relation to the speed of passag of the filaments between them, the necessary s pping action so as to promote the cutting of the filaments. The pressing roller may, however, be conveniently driven by its engagement with ther ating cutting roller, in which case its speed 1 ed by the speed of the driven roller, and .cases to some extent by the speed of passage of the filaments.

Cutting of the filaments can also be effected by an inversion of the arrangement just described,

i. e., by employing a cutting roller driven by con- 0 tact with a positively driven roller not necessarily having any cutting action. In this case the cutting roller presses itself against the filaments. Both rollers may be adapted to have a cutting action, suitable constructions of such an arrange- 5 ment being described hereafter.

Since continuity of the material as a whole must not be broken during the cutting of the filaments, the roller or rollers having the cutting action should not, under the pressure applied, 40 sever more than one or relatively few of the filaments in the material at any point along its length. Therefore, the cutting action of the roller or rollers must be limited under the'pressure conditions employed.

There may also be used for cutting the filaments a roller of an abrasive character, for example a roller or sleeve formed of emery, carborundum, or like abrasive material of fine to fairly coarse structure. The edges of the abrasive grains in the rollers engage filaments under the pressure applied and serve to sever filaments in turn in the bundle. Such rollers may be employed as driven members in conjunction with a non-cutting pressing member or as non-driven members or a pair of the abrasive rollers may be used together. Again, an abrasive roller may be used with a fluted roller as described in U. 8. application Ser. No. 23,804 filed May 28, 1935 as a division of the instant application. The moving cutting surface may also be provided in the form of an endless abrasive band suitably supported to allow the bundle to be pressed against it.

Where a non-cutting pressing roller is employed in conjunction with a cutting roller such as the abrasive rollers described above, this may be of non-resilient material and rigid in character, or it may be of resilient construction though preferably surfaced with some harder material. Thus, the pressing roller may comprise a core of rubber sponge or other soft rubber supporting a metal sleeve, the rubber affording a resilient mounting for such sleeve. In such case, the sleeve, however, is preferably thin enough, e. .g. 1/50, l/l00 inch or less to be itself flexible. Such a sleeve provides for long-life of the pressing roller. Polished steel tubing of the thickness mentioned is particularily suitable for use with the resilient core.

The one roller may be caused to exert the desired pressure on the other roller by positive loading, e. g. by a spring, weight or lever, but conveniently a self-loading roller of suitable weight may be employed, especially in view of the light pressure necessary to bring about the cutting action on the filaments. Such a roller is suitably mounted to rest by its own weight on the other roller and to rotate freely by its contact with such other roller. Rigid pressing rollers may be hollowed out to reduce their weight to enable them to give a light, self-loading pressure.

Instead of pressure being applied by a moving surface as provided by-a rotatable pressing roller, a stationary surface may be employed, as for example by a stationary member resting against the cutting surface and suitably loaded by its own weight or otherwise.

Control of the speed at which the filaments are caused to pass in contact with the cutting surface is preferably effected by another roller arrangement, e. g. a pair of rollers adapted to exert a firm grip on the filaments and rotatable at such speed in excess of the peripheral speed of the cutting roller or rollers that the desired slip is obtained past the cutting roller or rollers. Preferably a substantially non-slipping grip is provided at the gripping rollers so that these rollers determine the rate of progression of the filaments through the apparatus.

The filament bundle can thus pass between a pair of rollers forming a cutting device at a speed that, notwithstanding the different speed at which the cutting device is caused to operate, is substantially equal to the peripheral speed of a pair of gripping rollers between which they afterwards pass after severance of filaments in the bundle by the cutting device.

The gripping rollers may be made of any suitable material. For example they may be made of or surfaced with resilient material such asrubber, leather or cork, or one or more such rollers may work against a smooth or helically or otherwise fiuted roller, e. g. of metal, synthetic resins, cellulose acetate, or the like hard material. Again, rollers may be used having intermeshing grooves as described in U. S. patent application 8. No. 696,374. In all cases the nature of the grip applied by these rollers should be such as not to damage the filaments. Since, however, relatively little tension need be imparted to the filaments to cause them to slip under the light pressure at the cutting device, adequate grip can be imparted at the gripping rollers without unduly loading the rollers. Preferably, the tension in the filaments during the operation is insufficient to alter the physical characteristics of the filaments to any material extent. It is preferred to avoid any cutting action on thefilaments by the gripping rollers.

A convenient arrangement of gripping rollers comprises one roller having flutes parallel to the axis of the roller, which flutes are not sharp enough to cut the filaments, and another roller of relatively soft material such as medium hard rubber which presses the filaments firmly against the fluted roller.

Though both of the gripping rollers may be positively driven, it is convenient to drive one only, e. g. the fluted roller, and to press the other roller against it with the desired amount of pressure to exert firm grip on the filaments. This pressure may be effected either by the weight of the pressing roller or by means such as springs, weights, or levers. If desired, more than two rollers may be used to grip the filaments, for example two pressing rollers may be used with a single fluted roller.

The distance between the cutting device and the gripping device should be such that the bundle containing the severed filaments is brought under control of the gripping device soon after severance, the gripping device then serving to feed the bundle to a collecting device.

Collection is effected preferably by twisting to incorporate the fibers securely in the bundle. It is to be understood, however, that any twist originally in the bundle of filaments is not substantially removed by the operation of severing the filaments, and therefore remains in the bundle fed to the collecting device. Any additional twist imparted when collecting the bundle, as, for example, by winding the bundle by a cap or ring spinning device, is added to the remainder of such initial twist.

With the gripping device operating in a substantially non-slipping manner, the filament bundle may be converted into a fibrous bundle at a rate substantially equal to the peripheral speed of these rollers. At the same time, while there is pressure exerted on the filaments at the cutting device, the filaments may be able to slip over the cutting surface at a rate which may be substantially the same as the rate of delivery of the product from the gripping device. In other words, little, if any, elongation of the bundle need take place'in the operation, since the conversion of the filaments into fibers takes place largely by cutting and does not depend upon extension of the filaments to breaking point.

However, provided the physical properties of the filaments are substantially retained in the fibers produced, it is immaterial if a certain amount of reduction takes place in the size of the bundle during the passage of the filaments from the cutting device to the gripping device.

The conversion may take place over a wide range of speeds, e. g. thefibrous product may be formed at a rate ranging from a few feet per minute up to 50, 75, 100, 150 or more yards per minute. The invention therefore provides for the production of a fibrous yarn direct from continuous filaments in a very simple, rapid, and cheap manner.

It may be advisable, especially when operating at high speed and/or when applying relatively high twist to the product, to lubricate the yarn to assist the twisting and winding. Such lubrication may be effected. for example, by passing the yarn over 'a wick, roller, or other sup- 5 ply device between the gripping rollers and the twisting deviceor by spraying.

According to the invention, different kinds of continuous filaments may be converted into fibrous yarn, e. g. cellulose acetate or other cell lulose derivative filaments, natural silk filaments, and filaments of reconstituted cellulose, e. g. viscose, cuprammonium, and nitrocellulose filaments. Such filaments are of various deniers, e. g. 4 or or higher down to 1 denier or less, especially in the case of highly stretched filaments. Hollow filaments may be employed in the process according to the invention.

Normal artificial yarns may be subjected to i the operation, or if desired delustred or dull lustre yarns may be utilized. Thus, for example, there may be used cellulose acetate or other cellulose derivative yarns which have been subjected to a delustring treatment, for example by subjecting them to the action of hot or boiling aqueous liduors, or liquors containing thiocyanides or solvents or latent solvents; or cellulose acetate,

viscose, or other artificial yarns containing various percentages of pigments may be utilized either alone or in admixture with normal yarns. Again, different kinds of filaments may be simultaneously converted into staple fiber, for example natural silk filaments with cellulose acetate or viscose filaments, or cellulose acetate with viscose or other cellulosic filaments, so enabling differential or cross-dyed effects as well as other effects resulting from the difierences of materials to be obtained in the final product. For the same purpose spun yarns containing one type of fiber or mixture of fibers may be doubled with other spun yarns, including spun yarns .made

from natural fibers such as cotton or wool.

Again, the yarns produced according to the invention may be used in admixture with other types of natural or artificial yarns, for example, by plating with continuous filament yarns or with cotton or wool yarns in the production of knitted fabric. Also, yarns produced according to the invention but exhibiting diflerent characteristlcs may be used together, e. g. a yarn made frombright filaments may be plated with yarn made from dull or delustred filaments.

The invention also enables the characteristics of two or. more materials to be combined in the one yarn. Thus, using cellulose acetate filaments as the starting material, a yarn may be produced having the appearance of, say, wool or spun silk but in other respects having the characteristic properties of cellulose acetate artificial silk. Further, therange of materials available for many classes of weaving, knitting, and other textile operations is considerably extended.

The conditions of the cutting operation may be adjusted in accordance with the nature, condition, and denier of the filaments. For example, cellulose acetate filaments which are freshly spun by the dry method can be treated with the application of a lesser pressure at the cutting device than when the filaments have aged somewhat, possibly owing to a trace of residual solvent in the new filaments. For the same reason, some adjustment of the drying of cellulose acetate or other cellulose derivative filaments may be made in the dry-spinning or other process by which they are formed so as to condition the filaments for their conversion into fibers.

The filaments may also be specially conditioned before the operation.

subjection of the material to more than one cutting device brings about a reduction in average fiber length. Thus, material produced by one passage through an apparatus as above 'described may be passed again through the same or another apparatus, the twist in the material being suitably regulated to enable it to withstand the further cutting treatment. It is to be understood, therefore, that the expression yarn containing staple fiber used in the following claims to define the product into which the continuous filaments are converted does not necessarily connote that the product is immediately in a condition for the purpose for which it is finally intended; clearly, the product may be subjected to any further treatment before final use, such as, for example, the further cutting treatment just mentioned.

Again, additional twist may be added in a separate operation. For many purposes, however, adequate twist can be inserted as the final step of the operation in which the filaments are converted into the yarn containing staple fiber. Thus, about 3 turns per inch may be added by a cap spinning device to give a yarn particularly suited to use in knitting machines. although such twist is quite low for a staple fiber material, the strength of the yarn is quite considerable, probablydue to longer fibers being mixed with shorter ones.

The carrying out of the invention will now be described by way of example wig; referenceto the accompanying diagrammatic drawings, in which In fact,

Fig. 1 shows two pairs of cutting and gripping rollers disposed substantially horizontally with respect to each other;

Fig. shows pairs of cutting and gripping rollers disposed substantially vertically one above the other;

Fig. 3 shows a modified form of apparatus also utilizing a vertical disposition of the roller pairs; Fig. 4 is a detailed view of the cutting roller pair;

Fig. 5 shows a modified cutting device;

Figs. 6, 7, and 8 show apparatus utilizing a moving band as part of the cutting device; and

Figs. 9 to 11 show further views of diiferent forms of modified cutting devices.

Referring to Fig. 1, a bundle of filaments II) of suitable denier is fed between a pair of rollers II, I2 and then between a further pair of rollers I3, I4. The roller I4 is provided with smooth flutes and the roller I3 is covered with rubber or the like and suitably loaded so that the two rollers firmly grip the bundle. The roller I2 is provided with a' cutting surface, e. g. by having sharp-edged flutes, or by being made of or surfaced with an abrasive such as emery or carborundum. The roller I I lightly presses the bundle I0 against the periphery of the roller I2.

The roller I4 is driven at a speed in excess of. that of the roller I2, e. g. from 1 to 2, 3, 4, 5 or 6 or more times as fast, by chain and sprocket gearing Ill so that by reason of the firm grip exerted between the rollers I3, I4, the bundle I0 is caused to slip over the periphery of the cutting roller I2. By reason of the pressure between the rollers I I and I2 and the slip permitted by these rollers, the bundle drawn between the rollers has its filaments severed atlfrequent intervals so that after leaving the rollers I i, I2 the bundle contains staple fibers, the protruding ends of which are diagrammatically shown in the figure.

The rollers II, I 3 forming .the cutting device may rotate solely by their contact with the driven rollers I2, I4, it being understood, however, that an inversion of the roller arrangements is possible; 'for example the cutting roller I2 may rest upon and be driven by its contact with the noncutting roller II. Again, both rollers II, I2 may provide a cutting action.

Referring now to Fig. 2, the filament bundle I0 is shown supplied from a bobbin II and led to a pair of rollers I I, I2 as described with reference to Fig. 1. Gripping rollers I3, I4 are disposed below the roller I2 so that the bundle III passes over an arc of the roller I2 and vertically downwards to the nip of the rollers II, I l. The roller I3 is carried on an arm II pivoted at It and is pressed against the roller I4 by a cord 20 attached to the arm and carrying a weight 2| sufiicient to provide the gripping and preferably non-slipping action of the rollers I3, I4.

The arrangement of Fig. 2 thus provides the application of any desired amount of pressure at the pair of feed-rollers, while allowing for an independent amount of pressure being exerted between the rollers II, I2. Thus, the roller II can be self-loaded as shown in Fig. 4, the roller having a spindle 22 working in a slotted bearing 23 so that the roller II rests by its own weight on the roller I2.

The roller II may be rigid and so formed as to have the desired weight for the loading required, or it may consist of a resilient core 24, e. g. of sponge rubber or other soft rubber, within a flexible sheath 25, e. g. of thin metal tubing which provides a hard though flexible surface by which the filaments are pressed against the cutting periphery of the roller I2.

While one supply bobbin I5 only is shown in connection with Figure 2 it will be understood that bundles I0 from any number of bobbins or supply packages can be associated and fed to the cutting device for simultaneous treatment, the total denier or count of the several bundles being in accordance with the denier or count of the fibrous product required. Thus the bundle may be less than denier for the manufacture of very fine staple fiber yarns, or 100, 150, 200, 300, 1000, 2000 denier or more for the manufacture of heavier yarns.

The denier of the individual filaments may vary in accordance with the characteristics desired in the fibrous product. The bundles III may have little or not twist. or a small amount of twist, e. g. up to 2, 3 or 4 or so turns per inch, may be contained in the filament bundle.

In Fig. 3, the bundle III is supplied from a rotating bobbin It so as to add twist to the bundle before it is subjected to the action of the cutting device. Both rollers II, I3 are arranged to be pressed against their corresponding rollers I2, I I by the cord and weight arrangement 20, 2|. For this purpose the rollers II, II are mounted on a bar 25 pivotally mounted at 21 on the arm I8,

the point 28 at which the cord 20 is attached to the bar 26 preferably being adjustable in order that the requisite pressures may be exerted by the rollers II, I3 to provide for the cutting action of the one roller pair and the gripping action of the other respectively.

In Fig. 2 the yarn containing the staple fiber is shown being collected by a cap spinning device 29 operating to insert any desired amount of twist. In Fig. 3 collection is effected by a ring spinning device ll. While the collecting bobbins in connection with the spinningdevices are illustrated as being of parallel and cop form, respectively, it will be understood that any desired type of package may be formed, e. g. a package which enables the yarn to be used immediately in weaving, knitting or other fabric-forming operation. If desired, the yarn may be lubricated before being twisted, for example by carrying it over a wick I28, roller or other device supplied with lubricant and arranged between the rollers I3, I4 and the balloon guide 3| of the twisting device. Again, lubricant may be sprayed on to the yarn.

The distance between the rollers II, I2 and the gripping rollers I3, I 4 is such that the rollers I 2, I4 take control of the fibrous bundle soon after cutting so as to feed it continuously to the collecting device. While Figures 1 to 3 illustrate forms of apparatus in which one pressing roller (viz. I I) only is used in connection with each cutting roller I2 it will be understood that more than one pressing roller II could be used in connection with a single cutting roller. Thus, as shown inFlgure 11, two pressing rollers I I could be provided at different points on the peripheryof a single cutting roller I2, the filaments I0 passing over the arc of the cutting roller I2 extending between the two pressing points thus provided. Similarly, two cutting rollers may operate in contact with a single roller which may or may not be adapted to have a cutting action. There may be employed, on the other hand, two or more separate cutting devices through which the bundle III passes in turn.

In Fig. 5, the bundle III is carried into slipping contact with the cutting roller I2 by means of gripping rollers I3, I4 and the filaments are pressed against the roller I! by the surface of a stationary member 32 suitably weighted and carried in a slotted bearing 32 so as to rest on the roller I2. By reason of the pressure applied and the slippage of the bundle between the roller I2 and the member 32, the roller I 2 outs filaments in the bundle at frequent intervals.

Referring to Fig. 6, the cutting of the filaments is effected by means of an endless abrasive band 34 guided by rollers 35 and led over a roller 30, any or all of the rollers serving to drive the band. At the roller 38 the bundle l 0 is pressed in contact with the abrasive band 34 by means of a presser roller I I. The band 34 is driven at a speed different from that at which the bundle II is drawn by the rollers I3, I4 so that slippage of the bundle over the surface of the band takes place. The

- filaments pressed against the band by the roller I I are severed at frequent intervals.

In Fig. 7 an abrasive band 21 is carried and driven by rollers 38 to provide a horizontal run. Between the rollers 38 the, bundle II is pressed into contact with the abrasive surface of the band 31 by the roller II, the filaments being caused to slip over the band by the rollers I 3, It so that filaments are severed at frequent intervals.

In Fig. 8 an abrasive band 22 is carried over a stationary support 40 and driven by rollers II at a speed different from that at which the bundle I0 is drawn over the band and the support 40 by the rollers I3, I4. A roller II presses the bundle against the band 29 and the support ll so that filaments in the bundle are cut at frequent intervals.

Figure 9 shows a pair of cutting rollers 42 in contact with each other and driven by a chain 50, the bundle It being caused to pass between the rollers in slipping contact therewith by ripping rollers ll of the type described with reference to the preceding figures. The roller I4 is driven at a higher speed .thanthe cutting rollers 48 by a chain 5 l the bundle III thus being drawn between the cutting rollers at a higher speed than the peripheral speed of .the rollers. Figure 11 illustrates a pair of fluted cutting rollers 52 which are driven by chain and sprocket gearing 53. It will, of course, be understood that the fluted cutting rollers 52 can be used instead of or in addition to the cutting rollers II, I 2 described with reference to the preceding figures.

The average length of staple fiber-has an important bearing on the appearance and other qualities of the product produced according to the invention. This may be controlled by suitable adjustment of the apparatus and its conditions of operation, as well as by selection of the filaments to be treated. Thus, in general, a higher rate of operation of the apparatus results in a longer average fiber length being obtained. A greater amount of twist in the filament bundle tends to reduce the average fiber length. Again, greater pressure at the cutting device (this pressure depending also upon the size of the filament bundle to be treated) reduces the average fiber length, as also does an increase in the ratio between the speeds of the feeding and cutting devices. Finer filaments are usually more readily cut, and the more frequent breakage has the effect of reducing the average fiber length.

As indicated above, greater pressure at the cutting device is necessary with increase in the size of the filament bundle; Finer filaments, however, require less pressure than coarser filaments. Again, a lower ratio between the speeds of the feeding and cutting devices calls for higher pressure.

As regards the effect of the distance between the cutting and gripping devices on the length of staple, it may be noted that at the most only a small percentage of the fibers in the staple fiber yarn are less in length than this distance.

What we claim and desire to secure by Letters Patent is:-

1. Process for the conversion of continuous filaments directly into a product containing staple fiber, which comprises causing a bundle of continuous filaments to pass in contact with a cutting surface moving in substantially the same direction as said filaments but at a peripheral speed different from the speed of the filaments, and pressing the bundle against the surface so that during the movement of the surface the bundle is continuously nipped substantially at a point in its length and is subjected at such point.

to a cutting action that atany one point severs part only of the filaments in the bundle, the movement of the filaments past the cutting sur face causing the partial severing action to take place progressively along the length of the filaments.

2. Process for the conversion of continuous filaments directly into a continuous product containing staple fiber, which comprises causing a bundle of continuous filaments to pass in contact with the surface of a cutting roller moving in substantially the same direction as said filaments but at a peripheral speed difierent from the speed of the filaments, and pressing the bundle against the surface of the roller so that during the rotation of the roller the bundle is continuously nipped substantially at a point in its length and is subjected at such point to a cutting action that at any one point severs part only of the filaments in the bundle, the movement of the filaments past the surface of the roller causing the partial severing action, to take place progressively along the length of the filaments.

3. Process for the conversion of continuous filaments directly into' yarn containing staple fiber, which comprises causing a bundle of continuous filamentsto pass in contact with the surface of a cutting roller moving in substantially the same direction as said filaments but at a peripheral speed different from the speed of the filaments, pressing the bundle against the surface of the roller so that during the rotation of the roller the bundle is continuously nipped substantially at a point in its length and is subjected at such point to a cutting action that transforms the bundle into a staple fiber product of substantially the same denier or count as the bundle, the movement of the filaments past the surface of the roller causing the partial severing action to take place progressively along the length of the filaments, and collecting the product as a yarn by a twisting and winding operation.

4. Apparatus for the conversion of continuous filaments directly into a continuous product containing staple fiber, comprising a movable cutting surface, means for causing the bundle of continuous filaments to move over said surface, means with which the surface forms a nip at a point in the length of the surface of the roller, considered in the direction of the movement of the surface of the roller, to keep the filaments continuously pressed against the surface substantially at a point inthe length of the filaments, and means for causing the surface to move in substantially the same direction as the bundle but at a speed different from that of the bundle.

5. Apparatus for the conversion of continuous filaments directly into acontinuous product containing staple fiber, comprising a rotatable cutting roller, means for causing a bundle of continuous filaments to move over said roller, a rotatable roller with which the surface of the cutting roller forms a nip to keep the filaments continuously pressed against the cutting surface substantially at a point in the length of the filaments, and means for causing the cutting roller to rotate so that its surface moves in substantially the same direction as the bundle but at a speed different from that of the bundle.

6. Apparatus according to claim 5, comprising means to drive one of the contacting surfaces, the other roller being adapted to be driven by its contact with the driven roller.

'7. Apparatus for the conversion of continuous filaments directly into a product containing staple fiber, said apparatus comprising a rotatable cutting roller, means for causing the bundle of continuous filaments to move over said roller, a further rotatable cutting roller forming with the cutting surface of the first-mentioned roller a nip to keep the filaments continuously pressed against the two cutting surfaces substantially at a point in the length of the filaments, and means for causing the rollers to rotate so that their surfaces move in substantially the same direction as the bundle but at a speed different from that of the bundle.

8. Apparatus for the conversion of continuous filaments directly into a continuous product containing staple fiber, comprising a rotatable cutting roller having an abrasive surface, means for causing a bundle of continuous filaments to move over the surface of said roller, means with which the abrasive surface forms a nip at a point in the length of the surface of the roller, considered in the direction of the movement of the surface of the roller, to keep the filaments continuously pressed against the abrasive surface substantiallyat a point in the length of the filaments, and means for causing the roller to rotate so that its surface moves substantially in the same direction as the bundle but at a speed different from that of the bundle.

9. Apparatus for the conversion of continuous filaments directly into a continuous product containing staple fiber, comprising an endless abrasive band, means. for causing a bundle of continuous filaments to move over the surface of said band, means for pressing said bundle against said surface, and means for causing the band to move at a speed different from that of said bundle.

10. Apparatus for the conversion of continuous filaments directly into a continuous product containing, staple fiber, comprising a movable cutting surface, means for causing a bundle of continuous filaments to move over said surface, a hard flexible surfaced roller forming with the movable cutting surface a nip to keep the filaments continuously pressed against the cutting surface substantially at a point in the length of the bundle, the point of pressure progressing along the length of the bundle by reason of the movement of the bundle over the cutting surface, and means for causing the surface to move in substantially the same direction as the bundle but at a speed different from that of the bundle.

11. Apparatus for the conversion of continuous filaments directly into a continuous product containing staple fiber, comprising a rotatable cutting roiler, means for causing a bundle of continuous filaments to move over the surface of said roller, a hard flexible surfaced roller forming with the cutting roller a nip to keep the filaments continuously pressed against the cutting roller substantially at a point in the length of the bundle, the point of pressure progressing along the length of the bundle by reason of the movement of the bundle over the surface of the roller, and means for causing the cutting roller to rotate so that its surface moves in substantially the 

